Press the up arrow first or else the game won't work. Whenever you're stuck, just press the up arrow. Use arrow keys to move around. This is the first ever platformer project I have ever made, and for your information, this is very old. Check out my new and revised one: https://scratch.mit.edu/projects/1083940921/ Credits to @griffpatch for that one!
Credits to @vonder09, for helping me make this cool project, that has a few bugs and is pretty glicthy. I have the improved version on my profile called "Platformer (Work In Progress)", so feel free to experiment with it and check it out. I am adding more features to the new platformer like double jump, wall jumping, and levels. This is the platformer I discontinued. This is pretty old, you know. So feel free to go there right now. My new platformer!